type CommonState<Item> = {
    highlightedIndex: number;
    isOpen: boolean;
    selectedItem: Item | null;
    inputValue: string;
};
type CommonProps<Item> = {
    items: Item[];
    isItemDisabled: (item: Item, index: number) => boolean;
    itemToKey: (item: Item | null) => unknown;
    initialHighlightedIndex?: number;
    defaultHighlightedIndex?: number;
    defaultIsOpen?: boolean;
    defaultSelectedItem?: Item | null;
    defaultInputValue?: string;
};
type CommonAction<Item> = {
    type: string;
    index?: number;
    disabled?: boolean;
    highlightedIndex?: number;
    inputValue?: string;
    selectedItem?: Item | null;
};
type CommonStateChangeTypes = Record<string, string>;
export default function downshiftCommonReducer<Item>(state: CommonState<Item>, props: CommonProps<Item>, action: CommonAction<Item>, stateChangeTypes: CommonStateChangeTypes): CommonState<Item>;
export {};